AMF communities associated to Vitis vinifera in an Italian vineyard subjected to integrated pest management at two different phenological stages

Vitis vinifera L. is an economically important crop that can be influenced by soil microorganisms, including arbuscular mycorrhizal fungi (AMF), that establish symbiotic associations with its roots. AMF have beneficial effects on grapevine performance improving water use efficiency and replant success. Most grapevine varieties are susceptible to various diseases, and integrated pest management (IPM) is one of the emerging approaches to perform pest control. In the present study, we examined the AMF communities present in the soil associated to the roots of V. vinifera cv. Pinot Noir (comparing them to those present in a soil not affected by grapevine roots), in a vineyard subjected to IPM at two different phenological stages, using 454 Roche sequencing technology. We proposed a new approach to analyze sequencing data. Most of the taxa were included in the family Glomeraceae. In particular, Glomus sp. Rhizophagus sp. and Septoglomus viscosum were present. The family Archeosporaceae was represented only by the genus Archeospora sp. Different AMF communities were found in the two soils and the importance of the phenological stage in regulating AMF biodiversity was assessed.

Metaproteomic characterization of theVitis vinifera rhizosphere

The rhizosphere is a hotspot of microbial activity where the release of root exudates stimulates bacterial density and diversity. The majority of the bacterial cells in soil are viable, unculturable, but active. Proteomic tools could be useful in gaining information about microbial community activity and to better understand the real interactions between roots and soil. The aim of this work was to characterize the bacterial community associated with Vitis vinifera cv. Pinot Noir roots using a metaproteome approach. Our results confirmed the large potential of proteomics in describing the environmental microbial communities and their activities: in particular, we showed that bacteria belonging to Streptomyces, Bacillus, Bradyrhizobium, Burkholderia and Pseudomonas genera are the most active in protein expression. Concerning the biological activity of these genera in the rhizosphere, we observed the exclusive presence of the phosphorus metabolic process and the regulation of primary metabolic processes. To our knowledge, this is the first study reporting the rhizosphere proteome of V. vinifera, describing the bacterial community structure and activity of an important ecosystem for the Italian landscape, agriculture and economy.

Barriers against split-dose bowel preparation for colonoscopy

OBJECTIVE

Although split regimen is associated with higher adenoma detection and is recommended for elective colonoscopy, its adoption remains suboptimal. The identification of patient-related barriers may improve its implementation. Our aim was to assess patients' attitude towards split regimen and patient-related factors associated with its uptake.

DESIGN

In a multicentre, prospective study, outpatients undergoing colonoscopy from 8:00 to 14:00 were given written instructions for 4 L polyethylene glycol bowel preparation, offering the choice between split-dose and day-before regimens and emphasising the superiority of split regimen on colonoscopy outcomes. Uptake of split regimen and association with patient-related factors were explored by a 20-item questionnaire.

RESULTS

Of the 1447 patients (mean age 59.2±13.5 years, men 54.3%), 61.7% and 38.3% chose a split-dose and day-before regimens, respectively. A linear correlation was observed between time of colonoscopy appointments and split-dose uptake, from 27.3% in 8:00 patients to 96% in 14:00 patients (p<0.001, χ² for linear trend). At multivariate analysis, colonoscopy appointment before 10:00 (OR 0.14, 95% CI 0.11 to 0.18), travel time to endoscopy service >1 h (OR 0.55, 95% CI 0.38 to 0.79), low education level (OR 0.72, 95% CI 0.54 to 0.96) and female gender (OR 0.74, 95% CI 0.58 to 0.95) were inversely correlated with the uptake of split-dose. Overall, the risk of travel interruption and faecal incontinence was slightly increased in split regimen patients (3.0% vs 1.4% and 1.5% vs 0.9%, respectively; p=NS). Split regimen was an independent predictor of adequate colon cleansing (OR 3.34, 95% CI 2.40 to 4.63) and polyp detection (OR 1.46, 95% CI 1.11 to 1.92).

CONCLUSION

Patient attitude towards split regimen is suboptimal, especially for early morning examinations. Interventions to improve patient compliance (ie, policies to reorganise colonoscopy timetable, educational initiatives for patient and healthcare providers) should be considered.

TRIAL REGISTRATION NUMBER

NCT02287051; pre-result.

Neuromyelitis optica after a spinal anaesthesia with bupivacaine

We report the case of a 53-year old woman who developed a neuromyelitis optica (NMO or Devic’s syndrome) after a spinal anaesthesia with bupivacaine. To our knowledge, the use of bupivacaine in human has not been associated to neurological complications like myelitis or NMO. The patho genesis of this complication will be discussed.

[Drug treatment of early-stage (de novo and "honeymoon") Parkinson disease]

In this article, we discuss the management of motor symptoms during the early phases of Parkinson's disease, excluding that of any other clinical manifestation. We relied primarily upon recently published data and do not describe older publications relating to anticholinergic drugs or amantadine. The initial pharmacological treatment of idiopathic Parkinson's disease (IPD) is symptomatic and remains based upon dopaminergic drugs. However, the development of new drugs has broadened the range of strategic options and improved overall patient management. Announcing the diagnosis is a critical moment, as pointed out by patients' associations. Patients should be advised to maintain personal, professional, social and physical activities as long as possible. The potential benefit of early pharmacological treatment should be explained, focusing on the possible disease-modifying effect of drugs such as rasagiline. According to current guidelines, L-Dopa is preferred in patients above 65years of age, while those below 65 should be treated with dopamine agonists. Like monoamine oxidase inhibitors B (MAOI-B), synthetic dopamine agonists exhibit several advantages: easy-to-use treatment with a once-daily administration, delayed L-Dopa initiation, significant efficacy on motor symptoms (although lower than that of L-Dopa). MOAI can be prescribed in association with L-Dopa or dopamine agonists. Rasagiline also delays L-Dopa initiation, and consequently motor complications.

[Biotherapies and Parkinson's disease]

In the last years, several experimental biotherapies have been developed to treat Parkinson's disease. Initially, fetal dopaminergic transplants were proposed. Although a proof of concept and encouraging results have been provided, limitations of this treatment emerged over the years and the failure of controlled trials have conducted to a pause in the development of strategies based on fetal cells. Alternative approaches such as the use of retinal pigmented cells recently provided disappointing results in patients and much hope has now been reported on other sources of dopaminergic neurons such as those originating from stem cells. This strategy is however not yet ready for clinical trials in patients. Eventually, gene therapy is a new original experimental technique which has elicited several trials in the last few years some of them being promising.

Attempted and completed suicides after subthalamic nucleus stimulation for Parkinson's disease

A higher than expected frequency of suicide has been reported among patients undergoing subthalamic nucleus deep brain stimulation (STN DBS) for advanced Parkinson's disease (PD). We conducted a retrospective survey of 200 patients with PD who underwent STN DBS. Two patients (1%) committed suicide and four (2%) attempted suicide, despite clear motor improvements. Suicidal patients did not differ from non-suicidal patients with respect to age, disease duration or preoperative depressive and cognitive status. Suicidal behaviour was associated with postoperative depression and/or altered impulse regulation. Suicidal behaviour is a potential hazard of STN DBS, calling for careful preoperative assessment and close postoperative psychiatric and behavioural follow-up.

Chronic high dose transdermal nicotine in Parkinson's disease: an open trial

Whether nicotine has therapeutic effects on Parkinson's disease (PD) symptoms is controversial, but high doses and chronic treatment have never been tested. We report the results of a pilot, open-label trial to assess the safety and possible efficacy of chronic high doses of nicotine. Six patients with advanced idiopathic PD received increasing daily doses of transdermal nicotine up to 105 mg/day over 17 weeks. All patients but one accepted the target dose. Nausea and vomiting were frequent but moderate, and occurred in most of the patients (four of six) who received over 90 mg/day and 14 weeks of nicotine treatment. During the plateau phase, patients improved their motor scores and dopaminergic treatment was reduced. These results confirm the feasibility of chronic high dose nicotinic treatment in PD but warrant validation of the beneficial effects by a randomized controlled trial.

Hydrogen peroxide-related colitis (previously known as "pseudolipomatosis"): a series of cases occurring in an epidemic pattern

We report several cases of hydrogen peroxide-related colitis that occurred in an epidemic pattern in our gastrointestinal endoscopy center during a 2-month period in early 2007. During colonoscopy using sterilized endoscopes that had been flushed with hydrogen peroxide after the peracetic acid cycle, instantaneous effervescence and blanching (the "snow white sign") were observed on the intestinal mucosa when the water button was depressed. Biopsy specimens revealed features resembling a clinical condition which used to be known as "pseudolipomatosis." At follow-up, no patient was found to have suffered morbidity associated with this peroxide colitis. Endoscopists should consider hydrogen peroxide colitis when they see a snow white sign during colonoscopy which cannot be attributed to active inflammation or organic disease of the digestive tract.

[Neuropsychological impairment in the early Alzheimer's disease]

This analysis is centered on the study of cognitive disorders in Alzheimer's disease (AD), mainly for major neuro-psychological functions. We insist on the heterogeneity of the clinical picture peculiarly in the early stages of the illness, even if the deficits of episodic memory and of attentional/executive capacities are the first to deteriorate, preceding impairment in perceptual and language function and potentially having a substantial impact on the patient's capacity to cope independently. An episodic memory deficit is the hallmark of AD, but it must be stressed that this deficit may take different forms and its origin may be traced back to different cognitive mechanisms. One of the most striking aspects of episodic memory impairment in AD is the rapidity of forgetfulness on which screening and diagnostic tests of AD are based. There is some evidence that the episodic memory deficit in AD is one of learning (encoding and storage) of information rather than to a deficit of retrieval. Furthermore, episodic memory performance in AD depends on the integrity of semantic memory abilities, so giving support to a hierarchical model of organization of human memory. Finally, recent results show that an impairment of conscious recollection is responsible for the poor performance of AD patients in recognition memory. Executive deficits appear predominantly in tasks requiring cognitive flexibility and self-monitoring. With the progression of the disease, additional deficits are observed in the verbal concept formation abilities. These findings might be also very useful in the differential diagnosis between AD and the other cortical and subcortical dementias, as well as in the differentiation between AD and fronto-temporal dementia. We consider that studying early stages of the illness is necessary to delineate the diagnostic signs, to validate the new therapeutic experiments, to predict stages of decline. Recent research suggested that onset of AD is commonly preceded by an interim phase known as mild cognitive impairment (MCI). MCI refers to the clinical condition in which persons experience memory loss to a greater extent than one would expect for age, yet they do not meet currently accepted criteria for clinically probable AD. Persons who experience this condition are at increased risk for the development of AD. In MCI, despite the comparable global cognitive functioning, the findings show more impaired retrieval from long-term storage than in NC. The cued recall improves slightly the total recall but the recognition is significantly impaired. Moreover, the data indicate that MCI patients had additional problems with response inhibition, switching and cognitive flexibility. This suggests, that MCI may be identified by using a more detailed procedure for the assessment of cognitive decline than the evaluation of memory alone. As preventive strategies are developed and new cognitive enhancing therapies emerge, these results may also help us to define which domains are expected to improve in MCI populations.

Diagnostic and therapeutic impact of double-balloon enteroscopy (DBE) in a series of 100 patients with suspected small bowel diseases

BACKGROUND

Double-balloon enteroscopy is a newly developed endoscopic method allowing non-surgical full-length exploration of the small bowel, biopsies sample and endoscopic treatment of previously inaccessible lesions.

AIM

To prospectively assess the diagnostic and therapeutical impact of double-balloon enteroscopy in patients with suspected or documented small bowel disease.

PATIENTS AND METHODS

One hundred consecutive patients referring to our centre for suspected small bowel disease underwent double-balloon enteroscopy. Starting insertion route (anal or oral) of double-balloon enteroscopy was chosen according to the estimated location of the suspected lesions basing on the clinical presentation and on the findings, when available, of previous endoscopic or radiological investigations. Major indications for the procedures were acute recurrent or chronic mid-gastrointestinal bleeding (n=71), suspected gastrointestinal tumours (n=10), suspected Crohn's disease (n=6), chronic abdominal pain and/or chronic diarrhoea (n=8), refractory celiac disease (n=5).

RESULTS

One hundred and eighteen double-balloon enteroscopy procedures were carried out. Oral and anal route double-balloon enteroscopies were performed in 54 and 28 patients, respectively, while 18 patients underwent a combination of both approaches. Overall diagnostic yield of double-balloon enteroscopy resulted 69%. Most common pathological findings included angiodysplasias (n=39), ulcerations and erosions of various aetiologies (n=21), tumours (n=7) and ileal stenosis in patients with Crohn's disease suspicion (n=2). In the 65% of the patients examined, double-balloon enteroscopy findings influenced the subsequent clinical management (endoscopic, medical or surgical treatment). No major complications related to the procedure occurred.

CONCLUSIONS

Our prospective analysis shows that double-balloon enteroscopy is a useful, safe and well-tolerated new method with a high diagnostic and therapeutic impact for the management of suspected or documented small bowel diseases.

Les myélopathies secondaires aux fistules durales artério-veineuses peuvent-elles être aggravées par la corticothérapie intraveineuse ?

Dural fistulas are the most common vascular malformations of the spinal cord. They are of unknown origin but constitute a recognized cause of myelopathy. Aggravation of the clinical manifestations, either spontaneously or after invasive procedures, has been described. We report the case of a patient with a four-month history of myelopathic syndrome involving the lower limbs. Intravenous corticosteroid steroid treatment (1g) given for a suspected inflammatory disorder, induced a dramatic flare-up of the neurological symptoms which were reversible within 48 hours after corticosteroid withdrawal. The causal effect of the steroid treatment is discussed.

A highly accurate method for monitoring histological recovery in patients with celiac disease on a gluten-free diet using an endoscopic approach that avoids the need for biopsy: a double-center study

BACKGROUND AND STUDY AIM

Endoscopy with duodenal biopsy is often performed in order to assess histological recovery in patients with celiac disease who are on a gluten-free diet. Use of the "immersion" technique during upper endoscopy allows visualization of duodenal villi or detection of total villous atrophy. In this two-center study, we investigated the accuracy of the immersion technique in predicting histological recovery in patients on a gluten-free diet whose initial diagnosis of celiac disease had been made on the basis of total villous atrophy.

PATIENTS AND METHODS

The immersion technique was performed in 62 patients with celiac disease who were being treated and who had been referred for follow-up (26 patients at the Rome center and 36 patients at the Vicenza center). All these patients had an initial diagnosis based on positive antibodies and biopsy-proved duodenal total villous atrophy. At the follow-up examination, the duodenal villi were re-evaluated as present or absent by one endoscopist at each center, and the results were compared with the histology.

RESULTS

At the follow-up endoscopy, the duodenal villi were found to be present in 51 patients and absent in 11. The sensitivity, specificity, positive predictive value, and negative predictive value of the immersion technique for detecting the presence or absence of villi were all 100 %.

CONCLUSIONS

This study demonstrated the feasibility and the high level of accuracy of the immersion technique in predicting the histological recovery of duodenal villi in patients with celiac disease who are following a gluten-free diet. An endoscopy-based approach that avoids the need for biopsy could be useful for monitoring the dietary adherence and/or response of patients with an initial diagnosis of celiac disease based on total villous atrophy.

Diffusion-weighted MR imaging characteristics of an acute strokelike form of multiple sclerosis

The characteristics of multiple sclerosis (MS) lesions on diffusion-weighted sequences and apparent diffusion coefficient (ADC) mapping at the very early phase of symptoms have not been clearly described. We report the case of a young woman who presented with a sudden pseudostroke form of MS resulting in hemiplegia and sudden aphasia. MR imaging showed a lesion of the left internal capsule with reduced ADC, which suggests an ischemic stroke. This case shows that very acute MS lesions may have reduced ADC on MR imaging, reflecting cytotoxic and not vasogenic edema.

Accuracy of laryngeal examination during upper gastrointestinal endoscopy for premalignancy screening: prospective study in patients with and without reflux symptoms

BACKGROUND AND STUDY AIMS

Gastroesophageal reflux disease may be associated with laryngeal damage caused by reflux material. The aim of this study was to investigate the accuracy of laryngeal examinations during routine upper gastrointestinal endoscopy as a method of screening for major laryngeal injury in a series of patients with reflux symptoms.

PATIENTS AND METHODS

A total of 100 consecutive patients with reflux symptoms and 100 control individuals underwent upper gastrointestinal endoscopy with standard or high-resolution magnifying video endoscopes. Any laryngeal abnormalities were initially identified by the gastroenterologist before the scope was inserted into the esophagus. All of the examinations were recorded on video and subsequently reevaluated by an otorhinolaryngologist. All of the patients underwent standard laryngoscopy as a reference procedure.

RESULTS

All of the patients completed the study. The sensitivity, specificity, negative predictive value, and positive predictive value of the preliminary laryngeal exploration for detecting laryngeal abnormalities (such as laryngitis and vocal leukoplakia) were 90%, 90%, 92%, and 89%, respectively. High-resolution magnifying endoscopy had a higher sensitivity and specificity than standard endoscopy for detecting laryngeal pathology. Two patients were found to have laryngeal leukoplakia.

CONCLUSIONS

This study shows that preliminary diagnosis of laryngeal disorders can be accurately carried out by the gastroenterologist when patients are undergoing upper endoscopy for reflux symptoms. This approach could also be helpful for the timely diagnosis of major reflux-related laryngeal disease.

High accuracy and cost-effectiveness of a biopsy-avoiding endoscopic approach in diagnosing coeliac disease

BACKGROUND

The 'immersion' technique during upper endoscopy allows the visualization of duodenal villi and the detection of total villous atrophy.

AIM

To evaluate the accuracy of the immersion technique in detecting total villous atrophy in suspected coeliac patients. The accuracy in diagnosing coeliac disease and the potential cost-sparing of a biopsy-avoiding approach, based on selection of individuals with coeliac disease-related antibodies and on endoscopic detection of absence of villi, were also analysed.

METHODS

The immersion technique was performed in 79 patients with positive antibodies and in 105 controls. Duodenal villi were evaluated as present or absent. As reference, results were compared with histology. Diagnostic approaches, including endoscopy with or without biopsy, were designed to investigate patients with coeliac disease-related antibodies and total villous atrophy. A cost-minimization analysis was performed.

RESULTS

All patients with positive antibodies had coeliac disease. The sensitivity, specificity, positive and negative predictive values of endoscopy to detect total villous atrophy was always 100%. The sensitivity, specificity, positive and negative predictive values of biopsy-avoiding or biopsy-including strategies in diagnosing coeliac disease when villi were absent was always 100%. The biopsy-avoiding strategy was cost-sparing.

CONCLUSIONS

Upper endoscopy is highly accurate in detecting total villous atrophy coeliac patients. A biopsy-avoiding approach is both accurate and cost-sparing to diagnose coeliac disease in subjects with marked duodenal villous atrophy.

Neuroprotective gene therapy for Huntington's disease, using polymer-encapsulated cells engineered to secrete human ciliary neurotrophic factor: results of a phase I study

Huntington's disease (HD) is a monogenic neurodegenerative disease that affects the efferent neurons of the striatum. The protracted evolution of the pathology over 15 to 20 years, after clinical onset in adulthood, underscores the potential of therapeutic tools that would aim at protecting striatal neurons. Proteins with neuroprotective effects in the adult brain have been identified, among them ciliary neurotrophic factor (CNTF), which protected striatal neurons in animal models of HD. Accordingly, we have carried out a phase I study evaluating the safety of intracerebral administration of this protein in subjects with HD, using a device formed by a semipermeable membrane encapsulating a BHK cell line engineered to synthesize CNTF. Six subjects with stage 1 or 2 HD had one capsule implanted into the right lateral ventricle; the capsule was retrieved and exchanged for a new one every 6 months, over a total period of 2 years. No sign of CNTF-induced toxicity was observed; however, depression occurred in three subjects after removal of the last capsule, which may have correlated with the lack of any future therapeutic option. All retrieved capsules were intact but contained variable numbers of surviving cells, and CNTF release was low in 13 of 24 cases. Improvements in electrophysiological results were observed, and were correlated with capsules releasing the largest amount of CNTF. This phase I study shows the safety, feasibility, and tolerability of this gene therapy procedure. Heterogeneous cell survival, however, stresses the need for improving the technique.

Neurogenic pain relief by repetitive transcranial magnetic cortical stimulation depends on the origin and the site of pain

OBJECTIVE

Drug resistant neurogenic pain can be relieved by repetitive transcranial magnetic stimulation (rTMS) of the motor cortex. This study was designed to assess the influence of pain origin, pain site, and sensory loss on rTMS efficacy.

PATIENTS AND METHODS

Sixty right handed patients were included, suffering from intractable pain secondary to one of the following types of lesion: thalamic stroke, brainstem stroke, spinal cord lesion, brachial plexus lesion, or trigeminal nerve lesion. The pain predominated unilaterally in the face, the upper limb, or the lower limb. The thermal sensory thresholds were measured within the painful zone and were found to be highly or moderately elevated. Finally, the pain level was scored on a visual analogue scale before and after a 20 minute session of "real" or "sham" 10 Hz rTMS over the side of the motor cortex corresponding to the hand on the painful side, even if the pain was not experienced in the hand itself.

RESULTS

and discussion: The percentage pain reduction was significantly greater following real than sham rTMS (-22.9% v -7.8%, p = 0.0002), confirming that motor cortex rTMS was able to induce antalgic effects. These effects were significantly influenced by the origin and the site of pain. For pain origin, results were worse in patients with brainstem stroke, whatever the site of pain. This was consistent with a descending modulation within the brainstem, triggered by the motor corticothalamic output. For pain site, better results were obtained for facial pain, although stimulation was targeted on the hand cortical area. Thus, in contrast to implanted stimulation, the target for rTMS procedure in pain control may not be the area corresponding to the painful zone but an adjacent one. Across representation plasticity of cortical areas resulting from deafferentation could explain this discrepancy. Finally, the degree of sensory loss did not interfere with pain origin or pain site regarding rTMS effects.

CONCLUSION

Motor cortex rTMS was found to result in a significant but transient relief of chronic pain, influenced by pain origin and pain site. These parameters should be taken into account in any further study of rTMS application in chronic pain control.

[Treatment of Parkinson's disease by cell transplantation]

Brain transplantation of neurons may reach two different targets: (1) drug delivery system: eg dopaminergic (DA) neurons in Parkinson's Disease (PD) or indirect gene therapy in Huntington's disease (HD), and (2) organotypic reconstruction: eg striatal neurons in HD. Most published reports are phase 1, pilot trials: not all patients are responders, graft is followed by a 30p.100 decrease of daily levodopa intake, with an improvement of duration and severity of defined "off" periods and a decrease of the UPDRS score measured in "off". Only one phase 2 trial is completed. A moderate improvement of motor symptoms was observed along with a decrease of daily antiparkinsonian drug intake. PET imaging with labelled fluorodopa shows typically an increase of Ki, meaning an increase of uptake in the striatum as compared to the cortex. Dyskinesias seen in some patients suggest either a lesion effect into the striatum, or indicate that the heterotopy of the grafted neurons may be partially harmful to the motor pathways. Xenografts with porcine neurons led to poor survival. More than ten years following the first published results, whereas improvement of motor symptoms and reduction or cessation of dopaminergic drugs may be observed, transplantation remains a matter of technical and ethical concerns. It remains in the field of medical research. Many questions remain unanswered, namely: the best location and size of transplantation; the amount of grafted neurons; the need and duration of immunosuppressive treatments; the best source of neurons to be tarnsplanted and the long term effect as compared to other medical or surgical treatments. Nervertheless one can be convinced that this method may be not harmful to patients and thus deserves new clinical trials aimed at giving logical and documented answers to the many questions asked above.

[Neuron transplantation and Parkinson disease]

Brain transplantation of neurons may reach two different targets: (1) drug delivery system: e.g. dopaminergic (DA) neurons in Parkinson's Disease (PD) or indirect gene therapy in Huntington's disease (HD), and (2) organotypic reconstruction: e.g. striatal neurons in HD. Most published reports are phase 1, pilot trials: not all patients are responders, graft is followed by a 30 p. 100 decrease of daily levodopa intake, with an improvement of duration and severity of defined "off" periods and a decrease of the UPDRS score measured in "off". Only one phase 2 trial is completed. A moderate improvement of motor symptoms was observed along with a decrease of daily antiparkinsonian drug intake. PET imaging with labelled fluorodopa shows typically an increase of Ki, meaning an increase of uptake in the striatum as compared to the cortex. Dyskinesias seen in some patients suggest either a lesion effect into the striatum, or indicate that the heterotopy of the grafted neurons may be partially harmful to the motor pathways. Xenografts with porcine neurons led to poor survival. More than ten years following the first published results, whereas improvement of motor symptoms and reduction or cessation of dopaminergic drugs may be observed, transplantation remains a matter of technical and ethical concerns. It remains in the field of medical research. Many questions remain unanswered, namely: the best location and size of transplantation; the amount of grafted neurons; the need and duration of immunosuppressive treatments; the best source of neurons to be tarnsplanted and the long term effect as compared to other medical or surgical treatments. Nevertheless one can be convinced that this method may be not harmful to patients and thus deserves new clinical trials aimed at giving logical and documented answers to the many questions asked above.

[Paucisymptomatic and reversible myelinolysis after an anaphylactic shock]

Myelinolysis is characterized by a non inflammatory demyelination, affecting the central portion of the pons. Clinical features usually reflect damage to the descending motor tracts and include spastic tetraparesis, pseudobulbar paralysis, and the locked-in syndrome. We describe the case of a 58-year-old man, who developed a pontine and extrapontine myelinolysis, without hyponatremia, after an anaphylactic shock. Follow up demonstrated improvement of the clinical signs after a few days and the normalization of the MRI three months later. Our observation shows that a paucisymptomatic and spontaneously regressive myelinolysis can be the consequence of a state of shock.

Expression of protein kinase C beta1 confers resistance to TNFalpha- and paclitaxel-induced apoptosis in HT-29 colon carcinoma cells

The expression of different protein kinase C (PKC) isoenzymes has been shown to vary with proliferation rates, differentiation or apoptosis in normal colon crypts. In addition, the activity of some PKC isoenzymes appears to be reduced in colorectal cancer. The aim of the present work was to determine whether modulation of PKC expression would affect the susceptibility of a p53-defective colon carcinoma cell line to different apoptotic treatments. HT-29 cells exhibited sensitivity to paclitaxel (Taxol) and tumor necrosis factor alpha (TNFalpha) in a dose- and time-dependent manner but were relatively resistant to etoposide. Inhibition of PKC activity augmented the susceptibility of HT-29 cells to apoptosis, and phorbol ester induction of PKC reduced such susceptibility. Transfected HT-29(PKC) cells, hyper-expressing the beta1 isoform of PKC, were less sensitive to TNFalpha and paclitaxel than the normal counterpart. The present data 1) indicate that the expression of PKC influences the susceptibility of HT-29 colon cancer cells to apoptotic drugs apparently regardless of their mechanism of action, and 2) suggest paclitaxel as a potential candidate for the treatment of colon cancer, possibly in association with inhibitors of PKC (alpha and beta) at doses not cytotoxic per se.

Retest effects and cognitive decline in longitudinal follow-up of patients with early HD

OBJECTIVE

To assess the natural progression of cognitive impairment in Huntington's disease (HD) and to reveal factors that may mask this progression.

BACKGROUND

Although numerous cross-sectional studies reported cognitive deterioration at different stages of the disease, progressive cognitive deterioration has been, up to now, difficult to demonstrate in neuropsychological longitudinal studies.

METHODS

The authors assessed 22 patients in early stages of HD at yearly intervals for 2 to 4 years (average, 31.2 +/- 10 months), using a comprehensive neuropsychological battery based on the Core Assessment Program for Intracerebral Transplantation in Huntington's Disease (CAPIT-HD).

RESULTS

The authors observed a significant decline in different cognitive functions over time: these involved primarily attention and executive functions but also involved language comprehension, and visuospatial immediate memory. Episodic memory impairment that was already present at the time of enrollment did not show significant decline. The authors found a significant retest effect at the second assessment in many tasks.

CONCLUSION

Many attention and executive tasks adequately assess the progression of the disease at an early stage. For other functions, the overlapping of retest effects and disease progression may confuse the results. High interindividual and intraindividual variability seem to be hallmarks of the disease.

Motor and cognitive improvements in patients with Huntington's disease after neural transplantation

BACKGROUND

Huntington's disease is a neurodegenerative disease of genetic origin that mainly affects the striatum. It has severe motor and cognitive consequences and, up to now, no treatment. Motor and cognitive functions can be restored in experimental animal models by means of intrastriatal transplantation of fetal striatal neuroblasts. We explored whether grafts of human fetal striatal tissue could survive and have detectable effects in five patients with mild to moderate Huntington's disease.

METHODS

After 2 years of preoperative assessment, patients were grafted with human fetal neuroblasts into the right striatum then, after a year, the left striatum. Final results were assessed 1 year later on the basis of neurological, neuropsychological, neurophysiological, and psychiatric tests. The results obtained were compared with those of a cohort of 22 untreated patients at similar stages of the disease who were followed up in parallel. Repeated magnetic resonance imaging (MRI) and positron emission tomography (PET) scanning with fluorine-18-labelled fluorodeoxyglucose was also done to assess metabolic activity.

FINDINGS

The final PET-scan assessment showed increased metabolic activity in various subnuclei of the striatum in three of five patients, contrasting with the progressive decline recorded in the two other patients in the series, as seen in patients with untreated Huntington's disease. Small areas of even higher metabolic activity, coregistering with spherical hyposignals on MRI were also present in the same three patients, suggesting that grafts were functional. Accordingly, motor and cognitive functions were improved or maintained within the normal range, and functional benefits were seen in daily-life activities in these three patients, but not in the other two.

INTERPRETATION

Fetal neural allografts could be associated with functional, motor, and cognitive improvements in patients with Huntington's disease.

Neuroprotective gene therapy for Huntington's disease using a polymer encapsulated BHK cell line engineered to secrete human CNTF

Huntington's disease (HD) is an autosomal dominant genetic disease with devastating clinical effects on cognitive, psychological, and motor functions. These clinical symptoms primarily relate to the progressive loss of medium-spiny GABA-ergic neurons of the striatum. There is no known treatment to date. Several neurotrophic factors have, however, demonstrated the capacity to protect striatal neurons in various experimental models of HD. This includes the ciliary neurotrophic factor (CNTF), the substance examined in this protocol. An ex vivo gene therapy approach based on encapsulated genetically modified BHK cells will be used for the continuous and long-term intracerebral delivery of CNTF. A device, containing up to 106 human CNTF-producing BHK cells surrounded by a semipermeable membrane, will be implanted into the right lateral ventricle of 6 patients. Capsules releasing 0.15-0.5 microg CNTF/day will be used. In this phase I study, the principal goal will be the evaluation of the safety and tolerability of the procedure. As a secondary goal, HD symptoms will be analyzed using a large battery of neuropsychological, motor, neurological, and neurophysiological tests and the striatal pathology monitored using MRI and PET-scan imaging. It is expected that the gene therapy approach described in this protocol will mitigate the side effects associated with the peripheral administration of recombinant hCNTF and allow a well-tolerated, continuous intracerebroventricular delivery of the neuroprotective factor.

Dissociation between distal and proximal left limb agraphia and agraphesthesia in a patient with a callosal disconnection syndrome

A few neuropsychological studies have suggested the existence of bilateral hemispheric representations for the proximal parts of the limbs in humans. We report the case of a patient who presented with a callosal disconnection syndrome, which at a later stage of disease became restricted to left agraphia, left agraphesthesia and left auditory extinction. The anomic character of the agraphesthesia was demonstrated. Tactile naming was normal, which allows us to conclude that separate callosal pathways related to the left language areas transmit information for graphesthesia and tactile naming. Agraphia and agraphesthesia were not observed when the proximal part of the left upper limb was utilized. These observations support the conclusion that writing and graphesthesia with the proximal part of the limb can be mediated by the ipsilateral cortex.

Safety and tolerability assessment of intrastriatal neural allografts in five patients with Huntington's disease

This study describes issues related to the safety and tolerability of fetal striatal neural allografts as assessed in five patients with Huntington's disease. Huntington's disease (HD) is characterized by motor, cognitive, and behavioral disturbances. The latter include psychological disturbances and, as a consequence, we took particular care to analyze behavioral changes, in addition to the usual "safety" follow-up. We conducted multidisciplinary follow-up at least 2 years before and 1 year after grafting. Psychological care extended to close relatives. The grafting procedure itself was altogether safe and uneventful, and there were no apparent clinical deleterious effects for 1 year. The immunosuppressive treatment, however, was complicated by various problems (irregular compliance, errors of handling, side effects). Direct psychological consequences of the transplantation procedure were rare and not worrisome, although mood alteration requiring treatment was observed in one patient. Indirectly, however, the procedure required patients and relatives to accept constraints that tended to complicate familial situations already marred by aggressivity and depression. All patients and close relatives expressed major expectations, in spite of our strong and repeated cautioning. It is clearly important to be aware of these particular conditions since they may eventually translate into psychological difficulties in coping with the long-term clinical outcome of the procedure, if not beneficial. Despite an overall good tolerance, therefore, this follow-up calls for caution regarding the involvement of HD patients in experimental surgical protocols.

Primary somatosensory cortex activation is not altered in patients with ventroposterior thalamic lesions: a PET study

BACKGROUND AND PURPOSE

We know remarkably little about the mechanisms underlying cortical activation. Such mechanisms might be better understood by studying the effect of well-localized lesions on the cortical activations in simple paradigms.

METHODS

We used H(2)(15)O and positron emission tomography to measure regional cerebral blood flow (rCBF) at rest and during hand vibration in 7 patients with unilateral thalamic lesion involving the ventroposterior (VP) somatosensory thalamic relay nuclei. We compared the results with those obtained in 6 patients with thalamic lesions sparing the VP nuclei and 6 healthy controls.

RESULTS

The patients with VP lesions had a selective hypoperfusion at rest in the ipsilesional primary sensorimotor cortex (SM1). This hypoperfusion was significantly correlated with the degree of contralateral somatosensory deficit. This abnormality may reflect the deafferentation of SM1 from its somatosensory thalamic input. Despite this deafferentation, the ipsilesional SM1 was normally activated by the vibration of the hypoesthetic hand.

CONCLUSIONS

The fact that a lesion of the somatosensory thalamic relay nuclei alters the rCBF at rest in SM1 but not its activation by hand vibration indicates that the mechanism of cortical activation is complex, even in the case of simple sensory stimulation. In addition, a dissociation may occur between obvious neurological deficits and apparently normal activation patterns, which suggests that activation studies should be interpreted cautiously in patients with focal brain lesions.

Regulation of rat hepatocyte protein kinase C beta isoenzymes by the lipid peroxidation product 4-hydroxy-2,3-nonenal: A signaling pathway to modulate vesicular transport of glycoproteins

A major aldehydic end product of the peroxidation of arachidonic acid, 4-hydroxy-2,3-nonenal (HNE), has recently been considered for its potential involvement in a variety of cell functions. Here we report on the differential regulation of rat hepatocyte protein kinase C (PKC) isoforms by concentrations of HNE actually detectable in specific biological fluids or tissues. PKC betaI and, to a much greater extent, PKC betaII activities were markedly increased by 0.1 micromol/L HNE (final concentration in cell medium) whereas they were unaffected or even inhibited by 1 to 10 micromol/L HNE. On the contrary, the calcium independent PKC delta activity was inhibited by 0.1 micromol/L and increased by 1 and 10 micromol/L. Further, we show here that HNE-induced stimulation of PKC betaI and betaII activities, both in cytosolic and in membrane fractions, is paralleled by a marked stimulation of the anterograde transport of a lysosomal enzyme within the central vacuolar system. In fact, the treatment with 0.1 micromol/L HNE accelerated the PKC-dependent transport of lysosomal procathepsin D from the trans-Golgi network to the endosomal-lysosomal compartment and, in addition, increased the exocytosis of mature cathepsin D (CD) from these compartments. On the other hand, hepatocyte cotreatment with a selective inhibitor of classic PKCs prevented the aldehyde-induced activation of CD transport. These results support the possible involvement of HNE in the PKC-dependent regulation of the traffic of secretory glycoproteins, and point to remarkable implications of this aldehyde in the pathophysiology of various exocytic processes including hepatocyte lipoprotein secretion.

Somatosensory cortical activations are suppressed in patients with tactile extinction: a PET study

OBJECTIVE

To investigate whether tactile extinction alters the cortical somatosensory activations induced by hand vibration.

BACKGROUND

Tactile extinction occurs mainly after right-brain lesions and consists of the inability to perceive a contralesional cutaneous stimulation when a similar stimulus is applied to the mirror region of the ipsilesional hemibody. The pathophysiology of tactile extinction is poorly understood, but it is considered to be a deficit of selective attention of somatosensory stimuli. Although other theories have been proposed, our understanding of the pathophysiology of tactile extinction may benefit from functional imaging studies.

METHODS

We selected three patients with pure tactile extinction and a mainly subcortical right-brain lesion that spared the primary sensorimotor cortex (SM1). We used PET to investigate the responses to unilateral and bilateral hand vibration in SM1 and the secondary somatosensory cortical area (SII).

RESULTS

During bilateral hand vibration, activation was normal in the left SM1, suppressed in the right SM1, and markedly decreased in both SII, which was consistent with the extinction of the left-hand stimulus. During unilateral left-hand vibration, the activation of the right SM1 was still markedly impaired, but the activation of both SII was normal.

CONCLUSIONS

We found marked changes in the activation of cortical somatosensory areas induced by hand vibration in patients with tactile extinction. The role of selective attention in cortical activation is also examined.

Reciprocal interactions between intralaminar and lateral thalamic nuclei in rats

Reciprocal interactions between intralaminar thalamic nuclei (ncl. centralis lateralis, CL, and ncl. parafascicularis, Pf), the pretectal area (Pt) and lateral thalamic nuclei (ventrobasal complex, VB, ncl. anterior ventralis, AV, and ncl. ventralis anterior, VA) have been observed in ketamine-anaesthetized rats. Extracellular single unit activity has been recorded after single electrical stimuli. Electrical stimulation of the VB evoked a short latency orthodromic response followed by a pause in spontaneous activity in neurones of medial thalamic nuclei. Lateral thalamic neurones responded to electrical stimulation of the intralaminar nuclei or the pretectal area with the same pattern of response. Striatal, sensorimotor cortical or peripheral electrical stimulation also evoked similar responses. The pauses in spontaneous activity were shown to be the result of inhibition since the responsiveness of the intralaminar nuclei or the lateral thalamic neurones to all inputs was abolished or reduced after a conditioning electrical single-shock stimulation in the VB or in the intralaminar nuclei, respectively. The two components of the response were of a different origin, since most of the short latency responses disappeared after medullary, upper cervical sections or large decortications, while the inhibitions persisted. These inhibitions were shown to be of thalamic origin since their duration was decreased after extensive decortications increased after medullary section. It is concluded that the neuroneal properties studied in this report are probably broadly represented throughout the thalamus and that thalamic neurones are under inhibitory control elicited by afferent volleys. This inhibitory control includes a relay in the nucleus reticularis thalami (nRT). The mechanisms of sensory interaction can be purely thalamic, but they can be modulated by suprathalamic and/or mesencephalic loops.

Abnormal neuroneal activities in intralaminar thalamic nuclei following chronic lesions of nucleus reticularis thalami in rats

Extracellular single unit activity in the intralaminar thalamic nuclei (ncl. centralis lateralis, CL, n = 77 and ncl. parafascicularis, Pf, n = 163) and in the pretectal area (Pt, n = 75) was examined following chronic electrolytic lesions of the nucleus reticularis thalami (nRT) in ketamine-anaesthetized rats after single electrical stimuli to the ventrobasal complex (VB). Extensive alterations of either the ongoing ("spontaneous") activity or the pattern of VB evoked responses were observed. Four major changes were observed in the activity of these intralaminar or pretectal neurones: 1) many neurones were silent, two times more frequently than in a parallel study with control intact rats; 2) the firing pattern of all the other neurones was in the form of tonic (stationary-like) discharge, without burst discharges as previously described in intact animals. They were ranked into classes according to their spontaneous discharge: class I, silent (no resting discharge) 12%, class II (1-15 Hz), 54 % and class III (> 16 Hz), 34%. Class III neurones were never found in intact rats; 3) electrical stimulation of the VB evoked a short latency orthodromic excitatory response in these neurones but this response was not followed by any slowing or depression of the spontaneous activity in more than 40% of recorded cells. When it occurred, this pause was shorter than that always observed in intact rats by more than 35% and longer in 7% of the responsive cells. All these changes were correlated with the extent of damage to the ipsilateral nRT; 4) VB stimulation evoked prolonged excitatory responses lasting more than 150 ms in 13% of the responsive cells, and nRT stimulation led to a short latency response followed by a pause of activity. These findings suggest that the nRT is involved in sensory integration and modulation.

MRI-stereotactical approach for neural grafting in basal ganglia disorders

Optimization of the procedures for neural grafting is a timely issue, as this technique has proven beneficial for a few patients with late-stage Parkinson's disease in pilot studies and therefore may expand to become a more widely available therapeutic. In this research, one major issue is that of the placement of the cell deposits in the right target areas within the striatum. Although it is widely accepted that these suitable regions are the sensorimotor regions of the putamen, reliable delineation of these areas using classical stereotactical mapping techniques remains difficult. Along the course of a 5-year-long clinical transplantation program, we have developed an original procedure based on magnetic resonance imaging of the striatum on parasagittal views. This technique allowed us to identify precisely, and reproducibly in each patient, three subregions of the putamen (precommissural, commissural, and postcommissural) to be implanted. On the basis of the literature defining the sensorimotor putaminal regions in nonhuman primates, it was subsequently possible to extrapolate and localize these regions in each patient, thus providing a basis for the placement of cell deposits. Examples taken from our series of grafted patients demonstrate the value of this procedure that, in addition, minimizes interference of interindividual variability in the interpretation of clinical results.

Improvement of action tremor by chronic cortical stimulation

The authors present a patient who had long-term improvement of a severe upper limb action tremor after chronic cortical stimulation. A 40-year-old woman complained of facial pain and tremor of the left arm after removal of an acoustic neurinoma. A motor cortex stimulation was performed to treat the deafferentation facial pain in 1993. Chronic cortical stimulation induced complete relief of both pain and tremor and allowed the patient to recover functional capacity of the limb. These effects persisted throughout a 32-month follow up. Differential effects on pain and tremor were observed when parameters of stimulation were varied, suggesting different mechanisms for the relief of pain and tremor. Attention was focused on control of the tremor. This effect could be the result of the inhibition of subcortical structures which are involved in tremor. Chronic cortical stimulation appears to be an effective treatment for controlling severe action tremors.

Pain and its treatments

Among many relevant topics concerning pain and its treatments, the following will be considered: (1) definition of pain; (2) physiopathology; (3) methodology for clinical trials in pain research (4) use of drugs and surgical management of pain, and (5) future directions. The definition of pain as an unpleasant subjective, sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage, does not apply to living people incapable of self-report. Thus, nonverbal behavioral information is often needed and used for pain assessment. Major landmarks concerning physiopathology were: the liberation of substance P and other neuropeptides both at the spinal and peripheral endings, the anatomical and functional analysis of the nociceptive pathways, the characterization of endomorphins ligands and receptors. The difference between 'windup' and central sensitization were emphasized. Models of neuropathic pain have advanced our understanding of its specific pathophysiology. Sensoridiscriminative aspects of pain involve lateral thalamic nuclei and corresponding somesthetic cortices, whereas medial thalamic nuclei encode nociceptive stimuli during attention-directed tasks. Their cortical connections, namely anterior cingular cortex and insular cortex, support the postulate of a role in the affective-motivational dimensions of pain. An impressive increase in the number and quality of randomised clinical trials has been observed since 1950. The use of analgesics, opioids, antidepressants and other drugs is addressed, as well as new aspects concerning surgery or new drugs.

Treatment of deafferentation pain by chronic stimulation of the motor cortex: report of a series of 20 cases

Twenty patients with deafferentation pain were treated by chronic stimulation of the motor cortex. The central fissure was localized using stereotactic MRI and the motor cortex was mapped using intra-operative somatosensory evoked potentials. Seven patients with trigeminal neuropathic pain experienced definite pain relief varying between 40 and 100%. Ten patients had central pain secondary to central nervous system lesions. A satisfactory long-lasting pain control (pain relief > 40%) was obtained in five of them (50% of cases). One patient with pain from peripheral nerve injury obtained more than 80% pain relief. Two patients had pain from spinal cord lesions. One did not respond but the other obtained an excellent long-term result. The location of the effective stimulation plots was in agreement with the somatotopic maps of the primary motor cortex. One patient developed a small extradural haematoma which resolved spontaneously. None of the patients developed seizure activity. This study confirms the potential value of motor cortex stimulation in the treatment of certain forms of intractable pain, especially in cases with trigeminal neuropathic pain.

Improvement of severe postural cerebellar tremor in multiple sclerosis by chronic thalamic stimulation

Tremor can be particularly disabling in patients with multiple sclerosis (MS) and is mildly improved by drug treatment. The efficiency of stereotactic thalamotomy has been reported in a small number of patients but was counterbalanced by severe postoperative complications. Stimulation of the thalamic ventral intermediate nucleus, which is a less aggressive surgical method, is efficient in essential and in parkinsonian tremors. We report here the results of thalamic stimulation in 13 patients with MS with tremor. All patients were subjected to clinical examination, videorecording, and quantification of the functional disability before surgery and 3 months postoperatively. The surgical intervention was well tolerated in all cases. A clear improvement of the tremor was observed in 69.2% of the patients. Functional improvement was more varied and depended on the severity of tremor and coexistence of other neurological symptoms. Of the eight most severely affected patients, seven recovered the possibility to easily catch an object and use it. The results indicate that thalamic stimulation may be useful in the treatment of severe postural cerebellar tremor in MS.

[Neuropsychological testing of 5 patients with Parkinson's disease before and after neuron graft]

Five patients with idiopathic PD were followed by neuropsychological tests after brain fetal neuronal transplantation. The following tests were used in order to assess memory as well as visuospatial and frontal functions: MMSE, Mattis Scale, Wisconsin Card Sorting Test, Stroop task, word fluency tasks, 15-objects test, WAIS-R (Digit span, Arithmetic, Block design, Pictures completion, Pictures arrangement), learning of 15 words of Rey, WMS-R (Logical memory) and Visual memory of L. Israël. The same tests were performed before, then one year following the transplantation. Pooled data did not show any significant difference between pre and post-operative tests. Individual results varied among patients: 2 remained unchanged, 1 had a pathological deterioration which increased after one year, 1 had some frontal symptoms whereas the last patient improved. Our data confirm that this surgical procedure do not induce permanent neuropsychological deficits, but do not indicate at the present time any clear effect of dopamine reinnervation on cognitive functions.

Long-term outcome of unilaterally transplanted parkinsonian patients. I. Clinical approach

Five patients with Parkinson's disease, unilaterally transplanted with foetal mesencephalic cells into putamen (n=1) or putamen and caudate (n=4), were followed throughout a period of 15-36 months after surgery, according to the recommendations of the core assessment programme for intracerebral transplantations (CAPIT). All these patients exhibited an increase in the fluorodopa uptake in the grafted putamen, which was most significant in the first and last patient of the series. Long-term bilateral improvement of skilled hand movements was observed, starting between the third and sixth month after grafting, and confirmed by the statistical analysis of CAPIT timed tests. A mild to moderate effect on the amount of 'off' time and 'on-off' fluctuations was observed, whereas, apart from one case, no other clear effect on gait, walking and speech was found. One patient included in the study, already suffering slight cognitive impairment, clearly exhibited progression of a dementia process after surgery. Daily living activities were clearly improved in only one of the other four patients. At the end of the study period, all patients needed L-dopa therapy at a similar or higher dose than before grafting, but, in most of them, other dopaminergic drugs were reduced or stopped. All patients exhibited bilateral dyskinesias before grafting that were greatly decreased in intensity a few months after surgery. Delayed asymmetrical dyskinesias, occurring on the side displaying the better motor improvement, i.e. contralateral to the graft, were observed in three patients. These results suggest that neural transplants may influence two central mechanisms involved in motor function and the onset of dyskinesias. These effects are likely to occur through complex interactions with the post-synaptic dopaminergic receptors. The occurrence of dyskinesias might simply reflect increased presynaptic storage and release of dopamine. Alternatively, it might, in part, represent some other long-term deleterious effect of the graft. Since PET-scan data indicate that the reinnervation obtained is sub-optimal, it will be of interest to obtain a larger and denser reinnervation of the host striatum and to try, thereafter, to reduce the dose of L-dopa.